WPF DataBound treeview expand / collapse

Question

I\'m just trying to find a way to control the expand / collapse of the TreeView nodes through the object they\'re bound to. The object has an IsExpanded

Answer 1

Came up with solution. Really simple:

    <Style TargetType="{x:Type TreeViewItem}">
        <Setter Property="IsExpanded" Value="{Binding IsNodeExpanded}">
        </Setter>
    </Style>

So the style gets the object bound to the TreeViewItem and looks at its IsNodeExpanded attribute and it assigns that value to the TreeViewItem.IsExpanded property. If you add Mode=TwoWay, they'll notify each other (TreeViewItem will tell the object when it has been expanded).

Thanks!

Answer 2

FWIW, you may be interested in this CodeProject article by Josh Smith which shows how to create a MVVM based tree view using a generic (n-level) approach.

I'm not suggesting there is anything wrong with Carlo's implementation, but I found that article helpful in understanding the TreeView control, and MVVM in general.